Folding chair



Feb. 13, 1951 B. THAL 2,541,130

' FOLDING CHAIR Filed May 5, 1948 5 Sheets-Sheet l .lNVENTO/Q BERNARD THAL ATTORNEY B. THAL FOLDING CHAIR Feb. 13, 1951 5 Sheets-Sheet 2 Filed May 5, 1948 7 can /N\/E/VTOR BE RNARD T H A L 5 /W W ATTORNEY B. THAL FOLDING CHAIR Feb. 13, 1951 3 Sheets-Sheet 5 Filed May 5, 1948 BY flawed m A77 ORNE Y L m A TH N T D W m W N R E B 2 4 7/// Patented Feb. 13, 1951 UNITED STATES PATENT OFFICE FOLDING CHAIR Application May 5, 1948, Serial No. 25,269

27 Claims. 1

The present invention, though having also other fields of usefulness, relates more particuularly to folding chairs.

An object of the present invention is to provide a new and improved folding chair that shall be more rugged in construction and sturdy than folding chairs heretofore in use.

Another object is to improve upon the connections between the front legs and the mechanisms for simultaneously actuating the back and the rear legs of folding chairs.

Another object is to provide a new and improved mechanism for locking two relatively movable members against movement.

Other and further objects will be explained hereinafter and will be more particularly pointed out in the appended claims.

The invention will now be more fully described in connection with the accompanying drawings, in which Fig. 1 is an elevation of a chair embcdying the invention in preferred form, shown in fully open or extended or unfolded position; Fig. 2 is a similar view, showing the chair partly collapsed or closed; Fig. 3 is another similar View, showing the chair fully folded, collapsed or closed; Fig. i is a View similar to Fig. 2, upon a larger scale, but in vertical section upon the line 8-8 of Fig. 11, looking in the direction of the.

arrows, and with parts broken away, for clearness; Fig. 5 is a fragmentary view of the forward end of the link lever that is pivoted to the toggle, but upon a still larger scale; Figs. 6 and 7 are fragmentary views similar to Fig. a, but with the parts in relatively different positions, the scale being the same as in Fig. 5; Fig. 8 is a view similar to Fig. 4, but with the in still further different relative positions; Fig. 9 is a view similar to Fig. 7, showing further parts, upon a still larger scale and with the parts in the relative different positions shown in Fig. 8; Fig. 10 is a diagram explanatory of the operation of the parts when occupying the positions illustrated in Fig. 9; Fig. 11 is a fragmentary underside plan, upon a larger scale still; Fig. 12 is a similarly enlarged section taken upon the line i-i2 of Fig. 8, looking in the directions of the arrows; Fig. 13 is an underside perspective of the metal parts in the neighborhood of the hinge for pivoting one of the front legs; Fig. 14 is a perspective, upon a larger scale, of the mechanism shown in Fig. 9, showing also additional parts; and Fig. 15 is a section taken upon the line 5-1-5 of Fig. 8, looking upward, in the direction of the arrows, the scale being the same as in Fig. 11.

parts The folding chair of the present invention is of the type in which a back member I is pivoted at the rear of a horizontally disposed seat member 5 to fold toward and away from the upper side of the seat member 5, and rear legs 2 and front legs 3 are respectively pivoted at the rear and the front of the seat member 5 respectively to fold as units toward and away from the under side of the seat member 5. In chairs of this type, the back member I and the rear legs 2 foldforward and the front legs 3 fold simultaneously rearward to collapse or close the chair, and the back member I and the rear legs 2 fold rearward and the front legs 3 fold simultaneously forward to open the chair. The back member I may be constituted of the customary two wood side bars rigidly connected together to fold as a unit by wood cross bars, not shown. The two rear legs 2, if also of wood, may be similarly connected together rigidly by the customary wood cross bars, not shown, so as similarly to fold as a unit, and the same for the wood front legs 3.

As illustrated more particularly in Fig. 11, the seat member 5 may be provided with a threesided seat-supporting frame having wood side bars, rails or cleats 4, and a wood front bar, rail or cleat 43, the seat-supporting frame being open at the rear. The bars 4 and I3 may be secured together in any desired manner, as by means of glue, nails, screws and the like. The seat member 5 is shown secured in place in rabbeted or L-shaped grooves 9 provided in the side rails or bars l and the front rail or bar $3 of the seatsupporting frame by screws l l and 12. The seat member 5 is of substantially trapezoidal shape, as the front bar I3 is wider than the open space at the rear of the three sided seat frame. The side bars or cleats i are therefore inclined toward each other from the front toward the rear along the non-parallel sides of the trapezoid. As the legs 2 and 3 are positioned at the corners of this seat frame; the front legs 3 are therefore spaced farther apart than the rear legs 2, thus enabling the rear legs 2 to fold compactly between the front legs 3.

The long-stem or body portions of horizontally disposed rear T-shaped metal plates at are each provided with a pair of outwardly projecting horizontally disposed arms 5 between which the side bars, rails or cleats 4 are disposed, and an inwardly projecting arm 55. The plates 42 are fixed to the under side of the seat member 5 by securing them between and to the rear of the side bars, rails or cleats i, at the inner faces thereof, below the seating portion 5 of the seat, by bolts 33 that extend vertically through the side bars or cleats 4' and the arms 5d. The rear arms 5e are shown shorter than the front arms Ed in order that the plates 42 may be disposed in vertical planes at right angles to the parallel sides of the trapezoid. The back member I is shown pivoted at 4!, about an axis substantially parallel to the parallel sides of the trapezoid, to the upper arms of the Ts at the rear of and above the upper side of the seat member 5. The rear legs 2 are shown pivoted at 53, about an axis substantially parallel to the parallel sides of the trapezoid, to the lower arms of the Ts at the rear of and below the under side of the seat member. The pivots 4| and as are shown as rivets mounted in bushings M.

The front legs are also pivoted about an axis substantially parallel to the parallel sides of the trapezoid. This pivoting is effected through the medium of front-leg metal hinge plates 58 that may be secured in any desiredmanner, as by means of rivets 21, to the inner faces of the upper ends of the front legs, opposite to the rear legs 2. The upper ends of the plates 58 are shown provided with rolled-over cylinders 59 through which extend hinge pintles 2%. Though the cylinders 59 of each plate 58 are shown divided into two parts, axially alined substantiallly parallel to the parallel sides of the trapezoid, this is for convenience only. U-shaped metal hinge plates 22, provided with downward projecting terminal arms, are secured by rivets 2! to the under face of the seat member, at the corner junctions of the side bars 4 and the front bar 13, above the front legs 3. The pintles 23 extend not only through the cylinders 59, but also through the downward projecting terminal arms of the hinge plates 22. The metal plates 22 and 58 and the pintles 28 thus provide hinges by means of which the front legs 3 are pivoted below the seat member. The screws H and I2 for securing the seating portion 5 in place on the seat member extend respectively through the plates 22 and the inwardly projecting arms 55 of the T-shaped plates 42.

The rear end of each of two connecting or transfer link levers 6 is shown pivoted below the pivot 4i and above the pivot 43 to the front central pivot 3'1 of a toggle comprising two links 29 and 32. The front ends of the two toggle links 29 and 32 are pivoted to the central toggle pivot 3'5. Their rear ends are respectively pivoted at M and 5? to the back member 5 and the rear legs 2. The pivots 41 and 51, like the pivots 4i and 43, are shown as rivets mounted in bushings as. Each central toggle pivot 3'5 is mounted to slide in a horizontally disposed rear guide slot l9 provided in the long-stem or body portion of one of the T-shaped metal plates 42. It is therefore confined to movement parallel to the seat member 5 inthe vertical plane of the corresponding metal plate 42. By reason of this guided movement of the toggle pivot 31, any movement of the back member I must be communicated, through the toggle links 29 and 32, to the rear legs 2, and any movement of the rear legs 2 must similarly be communicated to the back member i. The back member i and the rear legs 2; are thus connected together by the toggles for simultaneous movement.

The front end of each connecting or transfer link lever 5 is shown provided with adjacently disposed cam portions 35 and 38, the former in front of the latter, a locking recess 39 disposed at the rear thereof, and an opening 25 elongated in a direction at an incline to the horizontal tween the pivot is and the pintle 23.

4 seat member, the incline extending downwardly from the front toward the rear of the chair. A pintle 23, illustrated in the form of a rivet, extends through the elongated opening 25 and also through a front guide slot ll, disposed in the longer arm of a front metal L-shaped guide or slide plate 8 the front and rear ends l6 and I8 of which are respectively secured to. the inner face of the side bar by rivets Hi. The longer arm of the L, between the rear rivet it and the offset bend 3! of the L, is disposed in a vertical plane substantially at right angles to the parallel sides of the trapezoid and to the rail or cleat l3,

a link M the front end of which is pivoted at.

E5 to a right-angularly-projecting lug 2% disposed at the lower end of each front-leg hinge plate 58. The pivots l5 are shown constituted of rivets extending through the link 14 and the lug 26. The lugs 2c are parallel to the longer parallel arms of the metal slide plate 8. As each link M therefore moves in a plane at right angles to'the front bar, rail or cleat l3, it is shown straight, without any offset bends be- This contributes to the rigidity'of the chair. By reason of the offset bends 3i, moreover, a space is provided between the longer arm of each metal plate 8 and the inner face of the side bar :3 to which it is secured in which the 'link M may be received'. Though not illustrated, the inner faces of the side bars 4 may be gouged out or recessed to receive the rear ends of the respective links M in the collapsed or closed position of the chair- As will hereinafter be more fully explained, the connecting or transfer link levers 6 are adapted to travel forward and rearward, in response to corresponding movement imparted to the toggle pivots 3 during the actuation toward and from each other of the back member I and the rear legs 2. During the forward travel of the link levers 6, the pintles 23 are confined to ride downward in the said vertically disposed planes of the longer arms of the L -shaped guide plates 8 along the inclines determined by the guide slots 1. During the rearward travel of the link levers 6, the pintles 23 are confined to ride upward along these inclines. The front legs 3 are therefore actuated about their pivoting pintles 28 into and out of collapsed or closed position, simultaneously with the actuation of the back member I and the rear legs 2, through the medium of the two connecting or transfer link levers 6.

A single connecting or transfer link lever 6 and associated mechanism would theoretically be effective for the purpose of folding and extending the rear and the front legs 2 and 3 rearward and forward as a unit and for simultaneously folding also the back member I but it is preferred to employ two connecting or transfer link levers 6, one at each side of the chair, connected in the same way to the respective front legs 3 and the corresponding toggle links 29 and 32.

Durlng'the forward movement of the. connecting or transfer link levers 5, stationary stud abutments 2%, shown as linkage-connecting-and locking rivets mounted upon the longer arms of the. respective L-shaped plates 8, will, after a time, become engaged, first by the cams 355, and then by the cams 33, at the forward ends of the link levers 5. Prior to the engagement of the earns 35 and 35 by the stud abutments 2d, the plntles 23 engage the lower end walls of the respective inclined openings 25, as illustrated in Fig. 4. Upon the cams 35 engaging. the stationary stud abutments 24, however, the forward ends of the link levers 6, during their further downward movement, will be caused to travel downward, from the position. of Fig. l, to that of Fig. 6. Such downward travel of the forward ends of the link levers G is permitted by the fact that the inclined openings 5 are elongated, with a component of the elongation in the up-and-down or vertical direction. In due course, therefore, the pintles 23 will bind against the upper walls of the respective elongated openings 23, as shown in Fig. 6, after which, during the further forward travel of the link levers 6, the cams 38 will engage the stationary stud abutments 24. In order to prevent binding, the cams 36 are constituted cl straight surfaces that are at this time par llel to the direction of inclination of the guide siots i.

Upon still further forward movement of the link levers 6, the cams 38 will ride past the respective stationary stud abutments 2 and the pintles 23 will come into contact with the lefthand end walls of the respective guide SL'Qt-s '5, though still remaining in contact with the upper ends of the respective inclined openings 25, as illustrated in Fig. 6. A fur her slight forward movement of the link levers 6 will cause the walls of the inclined slots 25 to ride upward at a for ward incline, in engagement with the respective pintles 23, from the position of Fig, 6 to that of Fig. 8. The pintles 23 thereupon reengage the lower end walls of the respective openings 25. The stationary stud abutments 2d at the same time become seated in the locking recesses 38 of the link levers all as shown in Fig. 8. Each link lever 5 becomes thereupon. loosed on its upper side by one of the stationary stud ahutments 24 becoming seated in one of the recesses 39, and on its lower side by the corresponding pintle 23 engaging against the bottom wall of one of the guide slots 3 and the upper wall of one of the inclined elongated openings The solid metal portion of the front end of the lever 6 between the lower portion of the elongated slot 25 and the ibcking recess 39 thereupon cooperates with the walls of the front guide slot 1! and the elongated slot to lock the chair open in the extended or unfolded position. The stationary stud abutments 24, therefore, serve as latches and the locking recesses 39 as cooperating latch recesses disposed near the front guide slots '5 to hold the connecting or transfer link levers 5 lock d in the position of Fig. 8. As the links H! serve also as front-leg braces when the chair is open or extended, the front legs 3 become locked against collapse in the open unfolded or extended position of the changes is also illustrated in 8. The pivots l5 and 2.3 are shown substantially alined with the stationary abutment 2A in the open position of the chair, but the chair will operate well even in the absence of this alinement.

This naturally serves, as well, to lock. the back member 1 and the rear legs 2 in the open unfolded or extended position of the chair. According to a featur of the present invention, however, the stability of the chair is increased by providing two additional locking mechanisms for locking both the back i the rear legs 2 inthe open unfolded or extended position of the chair.

One of the two additional mechanisms for looking the back i and the rear legs 3 in the open unfolded or extended position of the chair comprises a forwardly disposed locking latch 26 of each toggle link 32 for enteing into, in order to become lockingly seated in, a locking latch recess 48 of a catch pivoted at 58. The catches 39 are normally biased upward toward locking positions by a hand-release spring plate it, acting through connecting loci: extension rods 36 that are respectively pivoted to the catches 3d at 56. The spring plate as is h ld loosely to the inner face of. the front bar of the seat by headed pins 5! extending "through elongated openings 50 in curved spring end portions 52 provided at the ends of the spring plate 49. This locking against movement of the link 32 naturally results also in similarly locking the link 22*.

The other of the two additional locking mechanisms for locking the back i and the rear legs 2 in the open unfolded or extended position of the chair is obtained by providing each link 32 of each toggle with an intermediately disposed lock latch til for seating a corresponding intermediately disposed latch recess 5? of the other link 29 of toggle, when the links 23 and 32 of the toggles become collapsed.

If desired, it is possible to obtain still. additional locking effect by having the lower portion of the back member 5 engage solidi; against the upper portion of the rear legs 2, as shown more particularly in Figs. 1 and 9, and also to have both solidly against the rear faces of the side bars or cleats as is also illustrated in Fig. 1. It is found, however, a very efiec tive locking is secured without these aids.

Let it be assumed that the chair occupies its fully open, unfolded or extended position, illustrated in Figs. 1, S, 9 and 11. To collapse or close the chair, the back member 5 is grasped with one hand and the fingers of the other hand are pressed against the spring plate is toward the front bar it. The curved end portions 52 of the spring plate :33 yield as the walls of the elongated openings 55 ride past the headed pins 5!. The connecting rods 35 are thereupon moved forward. The spring bias provided by the spring plate 49 upon the catches through the connecting rods 35 being thus overcome, the catches are caused to move pivotally about their pivots 53 out of the position of Figs. 9, l!) and thereby releasing the latches 26 from the latch recesses 48 and unlocking the first of the two additional looking mechanisms of the chair bef re described.

Pressure may thereupon he applied to move the seat member 5 and the back member I ivotally forward toward eac other about the pivots 4!, from the open position of Figs. 1, 8, 9' and 11, through the partly collapsed position of Figs. 2 and 4-, toward the close or collapsed position of 3. Through the ac .on of the toggle links 253 and :32, this will result in corresponding movement of the rear legs 2 as a unit alz-out their pivots 43. The consequent rearward movement of the toggle pivots 3? in the horizontally disposed guide slots i9 will unseat the locking latches so from the latch recesses it from the. position of "Figs. 8, 9 and 14 toward the position of Fig. 4. It will result also in causing the connecting or transfer link levers 6 to move rearward, as above described. The stationary stud abutments it will therefore become unseated from their recesses 39, and the pintles 23 will become moved from the position of Fig. 8, out of engagement with the lower walls of the elongated slot 25 and the guide slot 7, into the position of Fig. 6. The catch 38 will at the same time assume the position shown in Fig. '7. With continued rearward movement of the connecting or transfer link levers 6, the pintles 23 will be caused to travel up their inclined guide slots 7, thereby drawing after them the links it from the position of Figs. 1 and 8, and through the position of Figs. 2 and 4, thus causing the front legs 3 to assume once more the collapsed position, illustrated in Fig. 3.

To fold open or extend the chair, all that is necessary is pivotally to move the back member l and the seat member away from each other about the pivots 4!. Upon the chair reassuming its fully open position, the front legs 3 will again become locked in place, the latches 48 will become reseated in the latch recesses H, and the spring ends 52 of the spring plate t9 will cause the connecting rods 36 to restore the bias of the catches 3i whereupon the latches 26 will become restored to their locking positions in the locking latch recesses 28, as illustrated in Figs. 8, 9, l and 1%. In order to facilitate the entry of the latches 26 into the latch recesses 38, their rear walls may be slightly inclined, as illustrated at :15, and the walls st of the latches 26 may be inclined to correspond.

Unless the plate ts is pressed toward the front bar l3, as before described, the chair, when open, will remain firmly locked open by the three looking mechanisms described above. Accidental unlocking is further safeguarded against, however, by the fact that, as shown more particularly in Fig. 10, at times when the chair is locked open, the pivots 53 and are alined with the latch 26. Unless the catch is released by pressure upon the spring plate d9, therefore, any movement of the back member 5 or the rear legs 2 tending to collapse the chair would result in the rear wall of the latch 2% binding against the cooperating engaging rear wall it of the latch recess 48, thereby resisting any such tendency to collapsing movement.

Modifications will occur to persons skilled in the art, and all such are considered to fall within the spirit and scope of the invention as defined in the appended claims,

'What is claimed is:

l. A folding. chair comprising a seat member provided with side bars, a back member pivoted above the upper side of the seat member at the rear of the seat member to fold toward and away from the upper side of the seat member, rear legs and front legs pivoted below the under side of the seat member respectively at the rear and. the front of the seat member respectively to fold as units toward and away from the under side of the seat member, a toggle connecting the back member and one of the rear legs the pivot of which is mounted to slide between the side bars below the under side of the seat membersubstantially parallel to the seat member, and means connecting one of the front legs with the toggle pivot for simultaneous folding of the back member and the rear legs forward and the front legs rearward to collapse the chair and for simultane- 8 ous folding of the back member and the rear legs rearward and the front legs forward to open the chair.

2. A folding chair comprising a seat member of substantially trapezoidal shape provided with side bars along its non-parallel sides, a back member pivoted at the rear of the seat member to fold toward and away from the upper side of the seat member about an axis substantially par allel to the parallel sides of the trapezoid, rear legs and front legs pivoted respectively at the rear and the front of the seat member respectively to fold as units toward and away from the under side of the seat member aboutaxes substantially parallel to the parallel sides of'the trapezoid, two guide members fixed between the 7 side bars to the under side of the seat member in planes substantially at right angles to the parallel sides of the trapezoid, a member guided by one of the guide members to move in one of the said planes between the side bars below the under side of the seat member, a toggle connecting the back member and one of the rear legs the pivot of which is guided by the other guide member to move in the other plane between the side bars below the underside of the seat member, and means connecting the guided member to the front legs and the toggle pivot for simultaneous folding of the back member and the rear legs forward and the front legs rearward to collapse the chair and for simultaneous folding of the back member and the rear legs rearward and the front legs forward to open the chair.

3. A folding chair comprising a seat member of substantially trapezoidal shape wider at the front than the rear and provided along its nonparallel sides with side bars inclining toward each other from the front toward the rear, 2. back member pivoted at the rear of the seat member to fold toward and away from the upper side of the seat member about an axis substantially parallel to the parallel sides of the trapezoid, rear legs and front legs pivoted respectively at the rear and the front of the seat member respectively to fold as units toward and away from the under side of the seat member about axes substantially parallel to the parallel sides of the trapezoid, two guide members fixed between the side bars to the under side of the seat member in planes substantially at right angles to the parallel sides of the trapezoid, a member guided by one of the guide members to move in one of the said planes between the side bars below the'under side of the seat member, a link disposed between the'said one side bar and the said one guide member connecting the guided member with one of the front legs, a toggle connecting the back member and one of the rear legs the pivot of which is guided by the other guide member to move in the other plane 'between the side bars below the under side of the seat member, and means connecting the guided member to the toggle pivot for simultaneous folding of the back member and the rear legs forward and the front legs rearward to collapse the chair and for simultaneous folding of the back member and the rear legs rearward and the front legs forward to open the chair.

4. A folding chair comprising a seat member of substantially trapezoidal shape wider at the front than the rear and provided along its nonparallel sides with side bars inclining toward each other from the front toward the rear, a

back member pivoted at the rear of the seat member to fold toward and awayfrom theupper 9 side of the seat member about an axis substantially parallel to the parallel sides of the trapezoid, rear legs and front legs pivoted respectively at the rear and the front of the seat member respectively to fold as units toward and away from the under side of the seat member about axes substantially parallel to the parallel sides of the trapezoid, two guide members respectively provided with front and rear guide slots fixed between the side bars to the under side of the seat member in planes substantially at right angles to the parallel sides of the trapezoid, a pivot member mounted in the front guide slot to slide in one of the said planes between the side bars below the under side of the seat member, a link disposed between the said one side bar and the guide member provided with the front guide slot connecting the pivot member with one of the front legs, a toggle connecting the back member and one of the rear legs the pivot of which is mounted in the rear guide slot to slide in the other plane between the side bars below the under side of the seat member, and a link con necting the pivot member to the toggle pivot for simultaneous folding of the back member and the rear legs forward and the front legs rearward to collapse the chair and for simultaneous folding of the back member and the rear legs rearward and the front legs forward to open the chair.

5. A folding chair comprising a seat member provided with front and rear guide slots, a back member pivoted at the rear of the seat member to fold toward and away from the upper side of the seat member, rear legs and front legs pivoted respectively at the rear and the front of the seat member respectively to fold as units toward and away from the under side of the seat member, a toggle connecting the back member and one of the rear legs the pivot of which is slidably mounted in the rear guide slot, means slidably mounted in the front guide slot, means connecting the slidably mounted means with the toggle and one of the front legs for simultaneous folding of the back member and the rear legs forward and the front legs rearward to collapse the chair and for simultaneous folding of the back member and the rear legs rearward and the front legs forward to open the chair, and means cooperating with the toggle to lock the chair open.

6. A folding chair comprising a seat member provided with front and rear guide slots, a back member pivoted at the rear of the seat member to fold toward and away from the upper side of the seat member, rear legs and front legs pivoted respectively at the rear and the front of the seat member respectively to fold as units toward and away from the under side of the seat member, a toggle connecting the back member and one of the rear legs the pivot of which is slidabiy mounted in the rear guide slot, means sliolably mounted in the front guide slot, and means connecting the slidably mounted means with the toggle and one of the front legs for simultaneous folding of the back member and the rear legs forward and the front legs rearward to collapse the chair and for simultaneous folding of the back member and the rear legs rearward and the front legs forward to open the chair, the toggle and the seat member being provided with a latch and a cooperating latch recess for receiving the latch.

7. A folding chair comprising a seat member provided with front and rear guide slots, a back membe pivo ed t the ear of the seat member to fold toward and away from the upper side of the seat member, rear legs and front legs pivoted respectively at the rear and the front of the seat member respectively to fold as units toward and away from the under side of the seat member, a toggle connecting the back member and one of the rear logs the pivot of which is slidably mounted in the rear guide slot, means slidably mounted in the front guide slot, a link connecting the siidably mounted means with one of the front legs, means connecting the slidably mounted means with the toggle for simultaneous folding of the back member and the rear legs forward and the front legs rearward to collapse the chair and for simultaneous folding of the back member and the rear legs rearward and the front legs forward to open the chair, and means 00-,- operating with the toggle and the link to look the chair open.

8. A folding chair comprising a seat member provided with front and rear guide slots, a back member pivoted at the rear of the seat member to fold toward and away from the upper side of the seat member, rear legs and front legs pivoted respectively at the rear and the front of the seat member respectively to fold as units toward and away from the under side of the seat member, means providing for simultaneous folding of the back member and the rear legs forward and the front legs rearward to collapse the chair and for simultaneous folding of the back member and the rear legs rearward and the front legs forward to open the chair comprising a toggle connecting the back member and one of the rear legs the pivot of which is slidably mounted in the rear guide slot, a lever the rear end of which is pivoted to the toggle pivot and the forward end of which is provided with means slidably mounted in the front guide slot, and a link connecting the slidably mounted means with one of the front legs, and means cooperating with the lever, the link and the walls of the front guide slot to lock the chair open.

9. A folding chair comprising a seat member provided with front and rear guide slots, a back member pivoted at the rear of the seat member to fold toward and away from the upper side of the seat member, rear legs and front legs pivoted respectively at the rear and the front of the seat member respectively to fold as units toward and away from the under side of the seat member, means providing for simultaneous folding of the back member and the rear legs forward and the front legs rearward to collapse the chair and for simultaneous folding of the back member and the rear legs rearward and the front legs forward to open the chair comprising a toggle connecting the back member and one of the rear legs the pivot of which is slidably mounted in the rear guide slot, a link the rear end of which is pivoted to the toggle pivot and the forward end of which is provided with an elongated opening, a pivot member slidably mounted in the front guide slot and disposed in the opening, and a link connecting the pivot member-with one of the front legs, and means cooperating with the links and the walls of the front guide slot and the opening to lock the chair open.

10. A folding chair comprising a seat member provided with front and rear guideslots and a latch disposed near the front guide slot, a back member pivoted at the rear of the seat member to fold toward and away from the upper side of the seatinember, rear legs and front legs ivoted respectively at the rear and the front of the seat member respectively to fold as units toward and away from the under side of the seat member, means providing for simultaneous folding of the back member and the rear legs forward and the front legs rearward to collapse the chair and for simultaneous folding of the back member and the rear legs rearward and the front legs forward to open the chair comprising a toggle connecting the back member and one of the rear legs the pivot of which is slidably mounted in the rear guide slot, alever the rear end of which is pivoted to the toggle and the forward end of which is provided with means slidably mounted in the front guide slot, and a link connecting the lever with one of the front legs, the forward end of the lever being provided with a latch recess, and means whereby the latch is caused to engage in the latch recess to lock the chair open.

v 11. A folding chair comprising a seat me1nber provided with front and rear guide slots and a latch disposed near the front guide slot, a back member pivoted at the rear of the seat member to fold toward and away from the upper side of the seat member, rear legs and front legs pivoted respectively at the rear and the front of the seat member respectively to fold as units toward and away from the under side of the seat member, and means providing for simultaneous folding of the back member and the rear legs forward and the front legs rearward to collapse the chair and for simultaneous folding of theback member and the rear legs rearward and the front legs forward to open the chair comprising a toggle connecting the back member and one of the rear legs the pivot of which is. slidably mounted in the rear guide slot, a lever the rear end of which is pivoted to the toggle and the forward end of which is provided with an opening inclined to the front guide slot, a pivotmember slidably mounted in the front guide slot and disposed in the opening, and a link connecting the pivot member with one of the front legs, the forward end of the lever being provided with a latch recess in which the latch is adapted to become seated when the chair is open, and the pivot member being adapted to become locked between the walls of the front guide slot and the opening to lock the chair open when the latch becomes seated in the recess.

12. A folding chair comprising a seat member provided with a guide slot and a latch disposed near the guide slot, a back member pivoted at the rear of the seat member to fold toward and away from the upper side of the. seat member,

rear legs and front legs pivoted respectively at the rear and the front of the seat member respectively to fold as units toward and away from the under side of the seat member, and means providing for simultaneous folding of the back member and the rear legs forward and the front legs rearward to collapse the chair and for simultaneous folding of the back member and the rear legs rearward and the front legs forward to open the chair comprising a lever the rear end of which is connected to the back member and one of the rear legs and the forward end of which is provided with means slidably mounted in the guide slot, and means connecting the lever and one of the front legs, the forward end of the lever being provided with a latch recess, and means whereb the latch is caused to engage the latch recess to lock th chair open. a

13. A folding chair comprising a seat member provided with a guide slot and a latch die posed near the guide slot, 8, back member pivot ed at the rear of the seat member to fold toward and away from the upper side of the seat member, rear legs and front legs pivoted respectively at the rear and the front of the seat member respectively to fold as units toward and away fromlthe under ide of the seat member, and means providing for simultaneous folding of the back member and the rear legs forward and the front legs rearward to collapse the chair and for simultaneous folding of the back mem-Z to the latch recess, the walls of the guide slot and the openin cooperating with the rear end of the link to lock the rear end of the link against movement in order to lock the said one front leg against collapsing movement when the latch is engaged in the latch recess, and the cam being adapted to engage the latch to unlock the rear end of the link upon a collapsing movement of the chair.

14. A folding chair comprising a, seat member provided with a guide slot and a latch disposed near the guide slot, a back member pivoted at the rearof the seat member to fold toward and away from the upper side of the seat member,

rear legs and front legs pivoted respectively at member and the rear legs forward and the front legs rearward to collapse the chair and for simultaneous folding of the back member and the rear legs rearward and the front legs forward to open the chair comprising means connecting the back member and one of the rear legs for simultaneous movement including a lever pro-' vided with an opening, and a link the forward end of which is pivoted to one of the front legs and the rear end of which is provided with a pivot member disposed in the guide slot and the opening, the lever being provided with a latch recess in which the latch is adapted to become engaged when the chair is open and a cam disposed adjacent to the latch, the walls of the guide slot and the opening cooperating with the pivot member to lock the rear end of the link against movement in order to lock the said one front leg against collapsing movement when the latch becomes engaged in the latch recess, and the cam being adapted to engage the latch to unlock the pivot member in, the front guide slot and the opening upon a collapsing movement of the chair.

15. A folding chair comprising a seat member provided with front and rear guide slots and a first latch disposed near the front guide slot, a back member pivoted at the rear of the seat member to fold toward and away from the upper side of the seat member, rear legs and front legs pivoted respectively at the rear and the front of the seat member respectively to fold as units toward and away from the under side of the seat member, means providing for simultaneous fold:

ing of the back member and the rear legs forward and the front legs rearward to collapse the chair and for simultaneous folding of the back member and the rear legs rearward and the front legs forward to open the chair comprising a toggle connecting the back member and one of the rear legs the pivot of which is slidably mounted in the rear guide slot, a lever the rear end of which is pivoted to the toggle and the forward end of which is provided with an opening at an angle to the front guide slot, and a link the forward end of which is pivoted to one of the front legs and the rear end of which is confined to ride in the front guide slot and the opening, the forward end of the lever being provided with a first latch recess in which the first latch is adapted to be come engaged when the chair is open, and a cam disposed adjacent to the latch recess, the walls of the front guide slot and the opening cooperating with the rear end of the link to lock the rear endof the link against movement in order to lock the said one front leg against collapsing movement when the first latch is engaged in the first latch recess, a catch pivoted to the seat, the toggle and the catch being provided with a second latch and a second latch recess, means for normally biasing the catch to cause the second latch to be received in the second latch recess in order to lock the chair open, and means for pivoting the catch in opposition to the action of the biasing means to release the second latch, the cam being adapted to engage the first latch to unlock the rear end of the link upon a collapsing movement of the chair.

16. A device for locking two relatively movable members against relative movement, one of the members being provided with a guide slot and a latch disposed near the guide slot, a lever mounted upon one of the members provided with an opening, a latch recess and a cam disposed adjacent to the latch recess, and a link pivoted to the other member having a pivot member disposed in the guide slot and the opening, the latch being adapted to become engaged in the latch recess upon a relative movement of the members in one direction, the walls of the guide slot and the opening cooperating with the pivot member to lock the pivot member in order to lock the members together when the latch is engaged in the latch recess, and the cam being adapted to engage the latch to unlock the pivot member in the guide slot and the opening upon a relative movement of the members in the opposite direction.

17. A folding chair comprising a seat member provided with a latch abutment, a horizontally disposed rear guide slot and a front guide slot that is inclined downward and forward, a back member pivoted at the rear of the seat member to fold toward and away from the upper side of the seat member, rear legs and front legs pivoted respectively at the rear and the front of the seat member respectively to fold as units toward and away from the under side ofthe seat member, means providing for simultaneous folding of the back member and the rear legs forward and the front legs rearward to collapse the chair and for simultaneous folding of the back member and the rear legs rearward and the front legs forward to open the chair comprising a toggle connecting the back member and one of the rear legs the pivot of which is slidably mounted in the rear guide slot, a lever the rear end of which is pivoted to the toggle and the forward end of which is provided with an, eloneated openingthat inclined downward and rearward, a pivot member slidably mounted in the front guide slot and disposed in the opening, and a link the forward end of which is pivoted to one of the front legs and the rear end of which is connected to the pivot member, the forward end of the lever being provided with a cam and a latch recess dis-- posed rearward of the cam, the latch abutment being adapted to become engaged by the cam during the opening of the chair and to become engaged in the latch recess when the chair is open, and the walls of the front guide slot and the opening cooperating with the pivot member to lock the rear end of the link against movement in order to lock the said one front legagainst collapsing movement when the latch abutment becomes engaged in the latch recess.

18. A folding chair comprising a seat member provided with front and rear guide slots, a back member pivoted at the rear of the seat member to fold toward and away from the upper side of the seat member, rear legs and front legs pivoted respectively at the rear and the front of the seat member respectively to fold as units toward and away from the under side of the seat member, means providing for simultaneous folding of the back member and the rear legs forward and the front legs rearward to collapse the chair and for simultaneous folding of the back member the rear legs rearward and the front legs forward to open the chair comprising a toggle connecting the back member and one of the rear legs the ivot of which is slidably mounted in the rear guide slot, a lever pivoted to the toggle provided with means slidably mounted in the front guide slot, and a link connecting the lever and one of the front legs, means for locking the back and the rear legs against collapsing movement when the chair is open, and additional means for looking the front legs against collapsing movement when the chair is open.

19. A folding chair comprising a seat member provided with front and rear guide slots, a back member pivoted at the rear of the seat member to fold toward and away from the upper side of the seat member, rear legs and front legs pivoted respectively at the rear and the front of the seat member respectively to fold as units toward and away from the under side of the seat member, means providing for simultaneous folding of the back member and the rear legs forward and the front legs rearward to collapse the chair and for simultaneous folding of the back member and the rear legs rearward and the front legs forward to open the chair comprising a toggle connecting the back member and one of the rear legs the pivot of which is slidably mounted in the rear guide slot, a lever pivoted to the toggle provided with means slidably mounted in the front guide slot, and a link connecting the lever and one of the front legs, means cooperating with the toggle to lock the back and the rear legs against collapsin movement when the chair is open, and additional means for locking the front legs against collapsin movement when the chair is open.

20. A folding chair comprising a seat member provided with front and rear guide slots, a back member pivoted at the rear of the seat member to fold toward and away from the upper side of the seat member, rear legs and front legs pivoted respectively at the rear and the front of the seat member respectively to fold as units toward and. away from the under side of the seat: member, means providing for simultaneous the front legs forward to open the chair comprisin a toggle connecting the back member and one of the rear legs the pivot of which is slidably mounted in the rear guide slot, a lever pivoted to the toggle provided with means slidably mounted in the front guide slot, and a link connecting the lever and one of the front legs, the links of the toggle being provided with means for locking the back and the rear legs against collapsing movement when the chair is open, and additional means for locking the front legs against collapsing movement when the chair is open.

21. A folding chair comprising a seat member, a back member pivoted at the rear of the seat member to'fold toward and away from the upper side of the seat member, rear legs and front legs respectively pivoted at the rear and the front of the seat member respectively to fold as units toward and away from the under side of the seat member, means providin for simultaneous folding of the back member and the rear legs forward and the front legs rearward to collapse the chair and for simultaneous folding of the back member and the rear legs rearward and the front legs forward to open the chair comprising a toggle connecting the back member and one of the rear legs and means connecting the toggle with one Of the front legs, and a catch, the catch and one of the links of the toggle being provided with a locking latch and a cooperating locking latch recess for locking the chair open.

22. VA folding chair comprising a seat member,

' a back member pivoted at the rear of the seat member to fold toward and away from the upper side of the seat member, rear legs and front legs pivoted respectively at the rear and the front of the seat members respectively to fold as units toward and away from the under side of the seat member, means providing for simultaneous folding of the back member and the rear legs forward and the front legs rearward to collapse the chair and for simultaneous folding of the back member and the rear legs rearward and the front legs forward to open the chair comprising a toggle comprisin two links pivoted together at one of their ends, the other ends of the links being respectively pivoted to the back member and one of the rear legs, and means connecting the toggle and one of the front legs, a pivoted catch, the catch and one of the links of the toggle being provided with a locking latch and a cooperating locking latch recess for looking the chair open, means for biasing the catch so as normally to receive the latch when the chair is open, and means for pivotally actuating the catch in opposition to the action of the biasing means to unlock the chair.

23. A folding chair comprising a seat member provided with front and rear guide slots, a back member pivoted at the rear of the seat member to fold toward and away from the upper side of the seat member, rear legs and front legs pivoted respectively at the rear and the front of the seat member respectively to fold as units toward and away from the underside of the seat memher, means providing for simultaneous folding of the back member and the rear legs forward and the front legs rearward to collapse the chair and for simultaneous folding of the back memher and the rear legs rearward and the front legs forward to open the chair comprising a toggle connecting the back member and one of the rear legs the pivot of which is slidably mounted in the rear guide slot, means slidably mounted in the front guide slot, and means connecting the slidably mounted means with the toggle and one of the front legs, a catch pivoted to the seat member, the toggle and the catch being provided with a latch and a cooperating latch recess for locking the chair open, means for biasing the catch so as normally to cause the latch to enter the latch recess when the chair is open, and means for pivotally actuating the catch in opposition to the action of the biasing means to unlock the chair.

24. A folding chair comprising a seat member provided with front and rear guide slots, a back member pivoted at the rear of the seat member to fold toward and away from the upper side of the seat member, rearlegs and front legs pivoted respectively at the rear and the front of the seat member respectively to fold as units toward and away from the under side of the seat member,

7 means providing for simultaneous folding of the back member and the rear legs forward and the front legs rearward to collapse the chair and for simultaneous folding of the back member and the rear legs rearward and the front legs forward to open the chair comprising a toggle connecting he back member and one of the rear legs the pivot of which is slidably mounted in the rear guide slot, a lever pivoted to the toggle provided with means slidably mounted in the front guide slot, and a link connecting the lever and one of the front legs, a catch pivoted to the seat member, the toggle and the catch being provided with a latch and a cooperating latch recess for looking the chair open, means for biasing the catch to cause the latch to enter the latch recess when the chair is open, and means for pivotally actuating the catch in opposition to the action of the biasing means to unlock the chair, the pivot of the catch and the pivotal connection of the toggle to the said one rear leg being substantially alined with cooperating engaging walls of the latch and the latch recess when the chair is open.

25. A folding chair comprising a seat member, a back member pivoted at the rear of the seat member to fold toward and away from the upper side of the seat member, rear legs and front legs pivoted respectively at the rear and the front of the seat member respectively to fold as units toward and away from the under side of the seat a member, means providing for simultaneous folding the'backmember and the rear legs forward and the front legs rearward to collapse the chair and for simultaneous folding of the back member and the rear legs rearward and the front legs forward to open the chair comprising a toggle comprising two links pivoted together at one of their ends, the other ends of the links being respectively pivoted to the back member and one of the rear legs, and means connecting the toggle and one of the front legs, and a pivoted catch, the catch and one of the links of the toggle being respectively provided with a locking latch and a cooperating latch recess for locking the chair open, the pivot of the catch and the pivot connecting the said one rear leg to the toggle being substantially alined with cooperating engaging walls of the latch and the latch recess when the chair is open.

26. A folding chair comprising a seat member,

a back member pivoted at the rearof the seat member to fold toward and away from the upper side of the seat member, rear legs and front legs pivoted respectively at the rear and the front of the seat member respectively to fold as units toward and away from the under side of the seat member, means providing for simultaneous folding the back member and the rear legs forward and the front legs rearward to collapse the chair and for simultaneous folding of the back member and the rear legs rearward and the front legs forward to open the chair comprising a toggle connecting the back member and one of the rear legs, and means connecting the toggle and one of the front legs, one of the links of the toggle being provided with a locking latch and the other link being provided with a cooperating locking recess for locking the chair open.

27. A folding chair comprising a seat member,

a back member pivoted at the rear of a seat member to fold toward and from the upper side of the seat member, rear legs and front legs respectively pivoted at the rear and the front of the seat member respectively to fold as units toward and away from the under side of the seat member, means providing for simultaneous folding of the back member and the rear legs forward and the front legs rearward to collapse the chair and for simultaneous folding of the back memher and the rear legs rearward and the front legs forward to open the chair comprising a toggle comprising two links pivoted together at one of their ends, the other ends of the links being respectively pivoted to the back member and one of the rear legs, and means connecting the toggle and one of the front legs, and a catch pivoted to the seat member, the catch and one of the links of the toggle being respectively provided with a locking latch and a cooperating latch recess for locking the chair open, means mounted upon the seat member for biasing the catch to cause the latch to enter the latch recess when the chair is open, and means mounted upon the seat member for pivotally actuating the catch in opposition to the action of the biasing means to unlock the chair, the pivot of the catch and the pivot connecting the said one rear leg to the toggle being substantially alined with cooperating engaging walls of the latch and the latch recess when the chair is open.

BERNARD THAL.

REFERENCES CITED The following references are of record in the file of this patent:

UNITED STATES PATENTS Number Name Date 938,315 Gundelach Oct. 26, 1909 1,922,305 Kovats Aug. 15, 1933 1,976,567 Kovats Oct. 9, 1934 1,981,387 Kovats NOV. 20, 1934 2,005,715 Kovats June 18, 1935 2,247,799 Boardman July 1, 1941 

